The present invention relates generally to aerial sensing systems and, more particularly, to an aerial platform with sensors to achieve high spatial, temporal and spectral resolution of a field of plants.
Traditional aerial platforms such as boom lifts, fixed-wing aircrafts and/or satellites present challenges in the application of remote sensing to plant performance monitoring. Conventional ladder or boom lifts are typically positioned too low above the field of plants (e.g., less than 50 feet altitude) to provide sufficient plant coverage and data collection. In contrast, satellites and aircraft are typically positioned too high above the field of plants (e.g., greater than 500 feet altitude). Moreover, images acquired by satellites are normally low in resolution both spatially and temporally. Aircraft based remote sensing systems generally cannot fly below certain altitudes and are not configured to provide images at the spatial resolutions typically required in phenotype screening of plants.
A helium balloon may fill the gap in altitudes between 50 feet to 500 feet (where ladder or boom-lifts are too low and manned aircraft are too high). Such balloon based image systems are known for use in crop monitoring systems. However, conventional balloon systems are normally effective only in relatively light wind conditions, and are difficult to position and hold steady. Moreover, accurately establishing a precise camera location or acquiring aerial images along an outline track remains challenging, if not impossible with conventional balloon-based imaging systems.
High-temporal frequency crop sensing demands a system that is able to collect large amounts of images of targeted fields. High-spatial resolution means that minor differences between targets of interest and their surroundings, such as soil backgrounds, are well established in each acquired image. Therefore, in processing high-temporal and high-spatial resolution images, one of the major challenges is to reliably, efficiently and accurately isolate a target/region of interest in large number of images.
High-throughput remote phenotype screening requires integration of aerial platforms with sensors to achieve high spatial, temporal and spectral resolution. Additionally, specific field references are required to precisely process the data and images acquired by the sensor system, resulting in the generation of reliable and accurate data for decision making The present disclosure describes an integrated system for remote sensing including an aerial platform, a sensor system, and an image processing system.
The present disclosure relates to a high-spatial and high-temporal resolution crop sensing system that consists of strategically position ground global positioning system (GPS) reference panels and a GPS guided low-elevation helium balloon based high performance crop sensing platform. High-throughput in-field phenotype screening demands sensors of high spatial, temporal, and spectral resolutions, as well as reliable platforms. Developments in sensors with high-spectral and spatial resolutions offer a unique opportunity in research on in-field high-throughput screening. Yet, traditional platforms, such as fixed-wing aircrafts and/or satellites, are not able to provide data of high enough resolution either spatially or temporally.
In an exemplary embodiment of the present disclosure, a system for monitoring a field of plants includes a plurality of ground based reference objects, each located at a known reference elevation, a known reference latitude, and a known reference longitude, and a balloon adapted to be positioned above the field of plants. The system further includes a balloon positioning system coupled to the balloon and configured to position the balloon relative to the field of plants. An imaging system is supported by the balloon and includes a location system which determines a balloon elevation, a balloon latitude, and a balloon longitude. The imaging system further includes at least one camera, and at least one gimbal configured to orient the at least one camera. The imaging system captures at least one image of the field of plants including the plurality of ground based reference objects in the at least one image.
In another exemplary embodiment of the present disclosure, a method of monitoring a field of plants is provided. The method illustratively includes the steps of positioning a plurality of ground based reference objects relative to the field of plants, each reference object being located at a known reference position including a known reference elevation, a known reference latitude, and a known reference longitude, and obtaining a first aerial image of the field of plants. The first aerial image is taken at a respective image position which corresponds to an image elevation, an image latitude, and an image longitude. The method illustratively further includes the step of assigning a position to each pixel in the first aerial image based on the image position and the known positions of the ground based reference objects captured in the first aerial image.
In a further exemplary embodiment, an aerial positioning system includes a balloon, a balloon positioning system coupled to the balloon and configured to position the balloon at a desired balloon elevation, a desired balloon latitude, and a desired balloon longitude. The balloon positioning system illustratively includes a plurality of winches supported on the ground, and a plurality of tethers extending between the winches and the balloon. A sensor system is supported by the balloon and includes a location system which determines a balloon elevation, a balloon latitude, and a balloon longitude. The sensor system further includes at least one sensor directed to a ground based region of interest, and at least one gimbal configured to orient the at least one sensor. A controller is in communication with the balloon positioning system and the sensor system, wherein the at least one sensor provides to the controller a first set of data related to the region of interest at a first time and a second set of data related to the region of interest at second time. The balloon positioning system positions the balloon at the desired balloon elevation, the desired balloon latitude, and the desired balloon longitude at both the first time and the second time in response to input from the location system.
In another exemplary embodiment, an aerial sensing system includes a plurality of ground based reference objects, each located at a known reference elevation, a known reference latitude, and a known reference longitude. The plurality of ground based reference objects each include a position reference panel having a unique identifier. An aerial platform is adapted to be position above a focus area including objects of interest. An aerial platform positioning system is coupled to the aerial platform and is configured to position the aerial platform at a desired aerial platform elevation, a desired aerial platform latitude, and a desired aerial platform longitude. An imaging system is supported by the aerial platform and includes a location system which determines an aerial platform elevation, an aerial platform latitude, and an aerial platform longitude. At least one camera obtains an aerial image of the objects of interest, the unique identifier being visible to the imaging system to identify the position reference panels. At least one gimbal is configured to orient the at least one camera. A position sensor is operably coupled to the gimbal for detecting the orientation of the at least one camera. The imaging system captures at least one image of the focus area including the plurality of objects of interest and the plurality of ground based reference objects in the at least one image. A controller is in communication with the aerial platform positioning system and the imaging system, the controller including a driving computer that controls the aerial platform positioning system in response to input from the location system, and an imaging computer that processes data from the at least one camera.
The above mentioned and other features of the invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings.